TimC wrote:I've changed my mind about flexible panels in the last few years. I think the first batches that manufacturers were marketing were not as durable as units manufactured recently. I don't have any first hand experience with flex panels as I used to believe the warnings about them so I steered away. Recently there have been good reports about the flex panels and I tend to now believe that if the panels are not handled regularly, like Cosmo did with his first ones, they will last a long time.
While heat build up does effect efficiency I don't think it hurts the panel physically to mount directly to a surface unless that panel is exposed to the direct sun continually. Obviously it is better to have ventilation under the panel since the cooler the panel stays the more efficient it will be. I have a rack mounted 1800 watt solar array at home and the panels will perform almost to rated capacity on a cold sunny winter day compared to around 85% of capacity on a hot sunny summer day. Panels mounted to a roof will often lose some efficiency due to heat buildup. It's not critical and most installations just put an extra panel or two to compensate for losses.
With the recent feedback I've read on flex panels I am considering one for my new Foamie roof instead of deploying a 100 watt panel I normally use.
Two things that keep me from mounting panels on my rig:
First: I have a DC/DC setup and when traveling, I'm charging. No matter what the weather. Love it!
Secondly: Orientation to the sun. You have to park in the sun and hopefully it's not hot climate your in. Then it's much easier to turn a portable setup for best gain then move the trailer (or in my case entire truck). Then comes angle to the sun. Tears are curved.. Square's well, how close to the equator are ya? Even folks I've met on the road with tilt panels, I wonder how much better gain over a good set of portable?
I've put my portable setup over my windshield in the southwest when I couldn't get shade. Block sun from my dash & gain power.. win/win. I have found so many places I could park in the shade and set out my portable in the sun. As we return from a hike, re-position it.
I'm sure others will say the 'Pros' of the mounted panels. I just don't see them.. 200w of panels and hope for 100w's of gain..
I'm a Portable panel dude, as you've noticed. I've debated the mounted over the years, yet I'm still a portable panel dude.
Only My Humble Opinion
Safe Travels!